I. Field
The following description relates generally to wireless communications, and more particularly to collecting consistent system information upon entering a cell in a wireless communication system.
II. Background
Wireless communication systems are widely deployed to provide various types of communication; for instance, voice and/or data can be provided via such wireless communication systems. A typical wireless communication system, or network, can provide multiple users access to one or more shared resources (e.g., bandwidth, transmit power, . . . ). For instance, a system can use a variety of multiple access techniques such as Frequency Division Multiplexing (FDM), Time Division Multiplexing (TDM), Code Division Multiplexing (CDM), Orthogonal Frequency Division Multiplexing (OFDM), and others.
Generally, wireless multiple-access communication systems can simultaneously support communication for multiple access terminals. Each access terminal can communicate with one or more base stations via transmissions on forward and reverse links. The forward link (or downlink) refers to the communication link from base stations to access terminals, and the reverse link (or uplink) refers to the communication link from access terminals to base stations. This communication link can be established via a single-in-single-out, a multiple-in-single-out or a multiple-in-multiple-out (MIMO) system.
MIMO systems commonly employ multiple (NT) transmit antennas and multiple (NR) receive antennas for data transmission. A MIMO channel formed by the NT transmit and NR receive antennas can be decomposed into NS independent channels, which can be referred to as spatial channels, where NS≦{NT, NR}. Each of the NS independent channels corresponds to a dimension. Moreover, MIMO systems can provide improved performance (e.g., increased spectral efficiency, higher throughput and/or greater reliability) if the additional dimensionalities created by the multiple transmit and receive antennas are utilized.
MIMO systems can support various duplexing techniques to divide forward and reverse link communications over a common physical medium. For instance, frequency division duplex (FDD) systems can utilize disparate frequency regions for forward and reverse link communications. Further, in time division duplex (TDD) systems, forward and reverse link communications can employ a common frequency region so that the reciprocity principle allows estimation of the forward link channel from the reverse link channel.
Wireless communication systems oftentimes employ one or more base stations that provide a coverage area. A typical base station can transmit multiple data streams for broadcast, multicast and/or unicast services, wherein a data stream may be a stream of data that can be of independent reception interest to an access terminal. An access terminal within the coverage area of such base station can be employed to receive one, more than one, or all the data streams carried by the composite stream. Likewise, an access terminal can transmit data to the base station or another access terminal.
Base stations in a wireless communication system can broadcast system information over a downlink. System information can indicate configuration and capability of a respective broadcasting base station. Further, system information can be received by an access terminal (or a plurality of access terminals).
System information for a base station can change at a modification period boundary. Typically, when an access terminal is camped on a base station and if system information is going to change in a next modification period (e.g., at a modification period boundary, . . . ), then the access terminal is paged for a system update. Thus, the access terminal can recognize that system information is to change based upon the received page, and the access terminal can collect updated system information during the next modification period.
However, when system information is initially being collected by an access terminal (e.g., when the access terminal is entering a base station and/or trying to camp on such base station, . . . ), the access terminal can be unaware of where a modification period boundary would be or if system information is going to change in a next modification period. For instance, under such a scenario, the access terminal can be unable to receive a page indicating system update. Conventional techniques oftentimes approach the foregoing by discarding system information received by the access terminal until modification period information is identified. Thereafter, upon identifying the modification period information, system information can be collected by the access terminal. Such an approach, however, can be inefficient and can yield delays associated with collecting system information.